Semiconductor device including SGT

Abstract

An SGT is formed that includes Si pillars. The SGT includes WSi2 layers serving as wiring alloy layers and constituted by first alloy regions that are connected to the entire peripheries of impurity regions serving as sources or drains located in lower portions of the Si pillars, are formed in a self-aligned manner with the impurity regions in a tubular shape, and contain the same impurity atom as the impurity regions and a second alloy region that is partly connected to the peripheries of the first alloy regions and contains the same impurity atom as the impurity regions.

The invention claimed is: 
     
       1. A semiconductor device including an SGT, comprising:
 a first semiconductor pillar that stands on a substrate in a direction vertical to a top surface of the substrate, 
 a first gate insulating layer surrounding the first semiconductor pillar; 
 a first gate conductor layer surrounding the first gate insulating layer; 
 a first impurity region below the first gate conductor layer in the vertical direction and connected to a portion inside the first semiconductor pillar or to a side surface of the first semiconductor pillar; 
 a first conductive layer surrounding an entire periphery of the first impurity region in a plan view; 
 a second conductive layer partly connected to a periphery of the first conductive layer in the plan view and extending parallel to the top surface of the substrate; 
 a third conductive layer connected to the first gate conductor layer, and 
 a fourth conductive layer, comprising a second portion of the first gate conductor layer, partly connected to a periphery of the third conductive layer in the plan view, and 
 extending in the direction parallel to the top surface of the substrate, and either partly overlapping the second conductive layer or not overlapping the second conductive layer in the plan view, 
 wherein at least one of the first conductive layer and the third conductive layer has an equal width in the plan view, and the fourth conductive layer has a rectangular-like shape in the plan view and a longitudinal center line thereof does not pass through a center point of the first semiconductor pillar. 
 
     
     
       2. The semiconductor device according to  claim 1 , wherein the fourth conductive layer has a lateral center line that intersects the longitudinal center line at a right angle in the plan view, and neither center line passes through the center point of the first semiconductor pillar. 
     
     
       3. The semiconductor device according to  claim 1 , wherein the second conductive layer has a rectangular-like shape in the plan view, and a longitudinal center line of the second conductive layer does not pass through the center point of the first semiconductor pillar. 
     
     
       4. The semiconductor device according to  claim 3 , wherein the second conductive layer has a lateral center line and a longitudinal center line that intersect at a right angle in the plan view, and neither center line passes through the center point of the first semiconductor pillar. 
     
     
       5. The semiconductor device including an SGT according to  claim 1 , wherein the first gate conductor layer and the third conductive layer are connected to each other in a self-aligned manner. 
     
     
       6. The semiconductor device including an SGT according to  claim 1 , further comprising a fifth conductive layer that is in contact with an inner side surface of the first conductive layer, is positioned between the first conductive layer and the first impurity region, and contains the same metal atom and donor or acceptor impurity atom as the first conductive layer. 
     
     
       7. The semiconductor device including an SGT according to  claim 1 , comprising:
 a second semiconductor pillar that vertically stands so as to be adjacent to the first semiconductor pillar; 
 a second gate insulating layer that surrounds the second semiconductor pillar; 
 a second gate conductor layer that surrounds the second gate insulating layer; 
 a second impurity region that is positioned below the second gate conductor layer in the vertical direction and is connected to a portion inside the second semiconductor pillar or to a side surface of the second semiconductor pillar; 
 a sixth conductive layer that surrounds the second impurity region in the plan view; and 
 a seventh conductive layer that surrounds the second gate conductor layer in the plan view, 
 wherein at least one of the sixth conductive layer and the seventh conductive layer has an equal width, 
 the second conductive layer is partly in contact with the sixth conductive layer, and 
 the fourth conductive layer is partly in contact with the seventh conductive layer. 
 
     
     
       8. The semiconductor device including an SGT according to  claim 7 , comprising:
 an eighth conductive layer that partly surrounds a periphery of the first conductive layer with an equal width in the plan view; 
 a ninth conductive layer that partly surrounds a periphery of the sixth conductive layer with an equal width in the plan view; and 
 a tenth conductive layer that lies between the first semiconductor pillar and the second semiconductor pillar in the plan view so as to be in contact with the first conductive layer, the sixth conductive layer, the eighth conductive layer, and the ninth conductive layer. 
 
     
     
       9. The semiconductor device including an SGT according to  claim 7 , comprising:
 an eleventh conductive layer that partly surrounds a periphery of the third conductive layer with an equal width in the plan view; 
 a twelfth conductive layer that partly surrounds a periphery of the seventh conductive layer with an equal width in the plan view; and 
 a thirteenth conductive layer that lies between the first semiconductor pillar and the second semiconductor pillar in the plan view so as to be in contact with the third conductive layer, the seventh conductive layer, the eleventh conductive layer, and the twelfth conductive layer. 
 
     
     
       10. The semiconductor device including an SGT according to  claim 1 , comprising:
 the first impurity region that surrounds a side surface of the first semiconductor pillar with an equal width in the plan view; and 
 the first conductive layer that surrounds the first impurity region with an equal width in the plan view. 
 
     
     
       11. The semiconductor device including an SGT according to  claim 1 , wherein at least one of the first conductive layer and the third conductive layer is constituted by a plurality of material layers having an equal width in the plan view. 
     
     
       12. The semiconductor device including an SGT according to  claim 1 , wherein the first conductive layer and the second conductive layer are formed of the same material and/or the third conductive layer and the fourth conductive layer are formed of the same material. 
     
     
       13. The semiconductor device according to  claim 1 , wherein the third conductive layer is formed of the same semiconductor material as the first gate conductor layer.